One factor behind the widespread acceptance and commercial success of personal computers (PC's) is expandability. Early PC's allowed expansion devices on AT cards to be plugged into an AT expansion bus inside the PC. Extra memory, disk drives, modems, network controllers, and a wide variety of creative devices could be added to the PC using such AT cards.
More recently updated expansion buses and ports have been incorporated into PCs. Hard disks may be attached to the PC using an integrated device electronics (IDE), Serial AT-Attachment (SATA), or a PCI-Express (PCIe) interface bus. Flash-memory devices the size of a pack of chewing gum or hidden inside an ink pen may be plugged into a Universal-Serial-Bus (USB) connector on the PC. Flash-memory cards that also fit inside digital cameras or music players can be plugged into a Multi-Media Card/Secure Digital (MMC/SD), Compact Flash (CF), Memory Stick (MS), or other flash-card reader slot to be read by the PC.
Many peripheral devices today use flash memory. Flash memory contains electrically-erasable programmable read-only memory (EEPROM) that is non-volatile. However, erase consumes a large amount of time, especially when compared to fast read times. Some flash memories may contain restrictions on the number of time data may be written between erase cycles, and other restrictions. The slow erase time and other restrictions limit the usefulness of flash memory peripherals.
What is desired is a peripheral device that uses non-volatile memory other than flash memory. A peripheral device for use with PC's and other systems is desirable that uses non-volatile memory with a faster write/erase time that is closer to the read time.